As a network system develops, requirements for a communication rate and a communication capacity gradually increase, and a requirement for high-frequency resources increases accordingly. However, a frequency increase is accompanied with an increase of phase noise generated by random jitter of a frequency component, namely, a local oscillator. Therefore, impact of the phase noise cannot be ignored in high-frequency wireless communication. Generally, a transmit end device may send a phase tracking reference signal (PTRS) that is known in advance, and a receive end may estimate phase noise based on the received PTRS.
When a plurality of terminal devices use a same PTRS sequence in one cell or sector, PTRS frequency domain positions to which the plurality of terminal devices perform mapping by using a same PTRS port are the same. In this case, different PTRSs mapped to a same frequency domain position interfere with each other, thereby affecting phase noise estimation. Therefore, how to randomize PTRS interference becomes an urgent problem to be resolved.